Test Procedure

KF1 KOEO AND KOER DTCS P0480 OR P1474: CHECK THE VPWR VOLTAGE TO LOW SPEED FC RELAY

LFC Relay connector disconnected.
Key in ON position.

Measure the voltage between:

(+) LFC Relay Connector, Harness Side	(-)
VPWR - Pin 1	Ground

Is the voltage greater than 10.5 V?

Yes	No
Key in OFF position. GO to KF2.	Key in OFF position. REPAIR the open circuit.

KF2 CHECK FOR LFC CIRCUIT CYCLING

Key in ON position.

Connect a non-powered test lamp between:

(+) LFC Relay Connector, Harness Side	(-) LFC Relay Connector, Harness Side
VPWR - Pin 1	LFC - Pin 2

Enter output test mode. Refer to OUTPUT TEST MODE (OTM) .
Command the low speed fan ON.
Command the high speed fan ON.
Command the outputs OFF.

Does the test lamp illuminate on and off when either the low or high speed cooling fan output is commanded on and off?

Yes	No
Key in OFF position. INSTALL a new LFC relay.	Key in OFF position. REMOVE the test lamp. GO to KF3.

KF3 CHECK THE LFC CIRCUIT FOR A SHORT TO POWER IN THE HARNESS

PCM connector disconnected.
Key in ON position.

Measure the voltage between:

(+) LFC Relay Connector, Harness Side	(-)
LFC - Pin 2	Ground

Is the voltage less than 1 V?

Yes	No
Key in OFF position. GO to KF4.	Key in OFF position. REPAIR the short circuit.

KF4 CHECK THE LFC CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS

Diagnostic tool connector disconnected.

Measure the resistance between:

(+) LFC Relay Connector, Harness Side	(-)
LFC - Pin 2	Ground

Is the resistance greater than 10K ohms?

Yes	No
GO to KF5.	REPAIR the short circuit.

KF5 CHECK THE LFC CIRCUIT FOR AN OPEN IN THE HARNESS

Measure the resistance between:

(+) LFC Relay Connector, Harness Side	(-) PCM Connector, Harness Side
LFC - Pin 2	LFC

Is the resistance less than 5 ohms?

Yes	No
INSTALL a new PCM. REFER to FLASH ELECTRICALLY ERASABLE PROGRAMMABLE READ ONLY MEMORY (EEPROM) .	REPAIR the open circuit.

KF6 KOEO AND KOER DTCS P0482 OR P1477: CHECK THE VPWR VOLTAGE TO MEDIUM SPEED FC RELAY

MFC Relay connector disconnected.
Key in ON position.

Measure the voltage between:

(+) MFC Relay Connector, Harness Side	(-)
VPWR - Pin 1	Ground

Is the voltage greater than 10.5 V?

Yes	No
GO to KF7.	Key in OFF position. REPAIR the open circuit.

KF7 CHECK FOR MFC CIRCUIT CYCLING

Key in ON position.

Connect a non-powered test lamp between:

(+) MFC Relay Connector, Harness Side	(-) MFC Relay Connector, Harness Side
VPWR - Pin 1	MFC - Pin 2

Enter output test mode. Refer to OUTPUT TEST MODE (OTM) .
Command the low speed fan ON.
Command the high speed fan ON.
Command the outputs OFF.

Does the test lamp illuminate on and off when either the low or high speed cooling fan output is commanded on and off?

Yes	No
Key in OFF position. INSTALL a new MFC relay.	Key in OFF position. REMOVE the test lamp. GO to KF8.

KF8 CHECK THE MFC CIRCUIT FOR A SHORT TO POWER IN THE HARNESS

PCM connector disconnected.
Key in ON position.

Measure the voltage between:

(+) MFC Relay Connector, Harness Side	(-)
MFC - Pin 2	Ground

Is the voltage less than 1 V?

Yes	No
Key in OFF position. GO to KF9.	REPAIR the short circuit.

KF9 CHECK THE MFC CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS

Diagnostic tool connector disconnected.

Measure the resistance between:

(+) MFC Relay Connector, Harness Side	(-)
MFC - Pin 2	Ground

Is the resistance greater than 10K ohms?

Yes	No
GO to KF10.	Key in OFF position. REPAIR the short circuit.

KF10 CHECK THE MFC CIRCUIT FOR AN OPEN IN THE HARNESS

Measure the resistance between:

(+) MFC Relay Connector, Harness Side	(-) PCM Connector, Harness Side
MFC - Pin 2	MFC

Is the resistance less than 5 ohms?

Yes	No
INSTALL a new PCM. REFER to FLASH ELECTRICALLY ERASABLE PROGRAMMABLE READ ONLY MEMORY (EEPROM) .	REPAIR the open circuit.

KF11 KOEO AND KOER DTCS P0481 OR P1479: CHECK THE VPWR VOLTAGE TO HIGH SPEED FC RELAY

HFC Relay connector disconnected.
Key in ON position.

Measure the voltage between:

(+) HFC Relay Connector, Harness Side	(-)
VPWR - Pin 1	Ground

Is the voltage greater than 10.5 V?

Yes	No
GO to KF12.	Key in OFF position. REPAIR the open circuit.

KF12 CHECK FOR HFC CIRCUIT CYCLING

Key in ON position.

Connect a non-powered test lamp between:

(+) HFC Relay Connector, Harness Side	(-) HFC Relay Connector, Harness Side
VPWR - Pin 1	HFC - Pin 2

Enter output test mode. Refer to OUTPUT TEST MODE (OTM) .
Command the low speed fan ON.
Command the high speed fan ON.
Command the outputs OFF.

Does the test lamp illuminate on and off when either the low or high speed cooling fan output is commanded on and off?

Yes	No
Key in OFF position. INSTALL a new HFC relay.	Key in OFF position. REMOVE the test lamp. GO to KF13.

KF13 CHECK THE HFC CIRCUIT FOR A SHORT TO POWER IN THE HARNESS

PCM connector disconnected.
Key in ON position.

Measure the voltage between:

(+) HFC Relay Connector, Harness Side	(-)
HFC - Pin 2	Ground

Is the voltage less than 1 V?

Yes	No
Key in OFF position. GO to KF14.	Key in OFF position. REPAIR the short circuit.

KF14 CHECK THE HFC CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS

Diagnostic tool connector disconnected.

Measure the resistance between:

(+) HFC Relay Connector, Harness Side	(-)
HFC - Pin 2	Ground

Is the resistance greater than 10K ohms?

Yes	No
GO to KF15.	REPAIR the short circuit.

KF15 CHECK THE HFC CIRCUIT FOR AN OPEN IN THE HARNESS

Measure the resistance between:

(+) HFC Relay Connector, Harness Side	(-) PCM Connector, Harness Side
HFC - Pin 2	HFC

Is the resistance less than 5 ohms?

Yes	No
INSTALL a new PCM. REFER to FLASH ELECTRICALLY ERASABLE PROGRAMMABLE READ ONLY MEMORY (EEPROM) .	REPAIR the open circuit.

KF16 KOEO AND KOER DTCS P0480 OR P1474: CHECK THE VPWR VOLTAGE TO LFC1 RLY

NOTE: This application has 2 relays wired to the LFC circuit. This procedure may call out LFC1 and LFC2 relays. Either of the relays may be used as the number 1, with the other relay being number 2.

LFC1 Relay connector disconnected.
Key in ON position.

Measure the voltage between:

(+) LFC1 Relay Connector, Harness Side	(-)
VPWR	Ground

Is the voltage greater than 10.5 V?

Yes	No
Key in OFF position. GO to KF17.	Key in OFF position. REPAIR the open circuit.

KF17 CHECK FOR LFC CIRCUIT CYCLING

Connect a non-powered test lamp between:

(+) LFC1 Relay Connector, Harness Side	(-) LFC1 Relay Connector, Harness Side
VPWR	LFC

Enter output test mode. Refer to OUTPUT TEST MODE (OTM) .
Command the low speed fan ON.
Command the high speed fan ON.
Command the outputs OFF.

Does the test lamp illuminate on and off when either the low or high speed cooling fan output is commanded on and off?

Yes	No
INSTALL a new LFC1 RLY. LEAVE RLY disconnected. GO to KF22.	Leave the test lamp connected GO to KF18.

KF18 CHECK FOR LFC CIRCUIT CYCLING WITH THE LFC2 RLY DISCONNECTED

Connect a non-powered test lamp between:

(+) LFC1 Relay Connector, Harness Side	(-) LFC1 Relay Connector, Harness Side
VPWR	LFC

LFC2 Relay connector disconnected.
Command the low speed fan ON.
Command the high speed fan ON.
Command the outputs OFF.

Does the test lamp illuminate on and off when either the low or high speed cooling fan output is commanded on and off?

Yes	No
INSTALL a new LFC2 relay.	GO to KF19.

KF19 CHECK THE LFC CIRCUIT FOR A SHORT TO POWER IN THE HARNESS

PCM connector disconnected.
Key in ON position.

Measure the voltage between:

(+) LFC1 Relay Connector, Harness Side	(-)
LFC	Ground

Is the voltage less than 1 V?

Yes	No
Key in OFF position. GO to KF20.	Key in OFF position. REPAIR the short circuit.

KF20 CHECK THE LFC CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS

Diagnostic tool connector disconnected.

Measure the resistance between:

(+) LFC1 Relay Connector, Harness Side	(-)
LFC	Ground

Is the resistance greater than 10K ohms?

Yes	No
GO to KF21.	REPAIR the short circuit.

KF21 CHECK THE LFC CIRCUIT FOR AN OPEN IN THE HARNESS

Measure the resistance between:

(+) LFC1 Relay Connector, Harness Side	(-) PCM Connector, Harness Side
LFC	LFC

Is the resistance less than 5 ohms?

Yes	No
INSTALL a new PCM. REFER to FLASH ELECTRICALLY ERASABLE PROGRAMMABLE READ ONLY MEMORY (EEPROM) .	REPAIR the open circuit.

KF22 VERIFY THERE IS NOT AN OPEN IN THE CIRCUIT SPECIFIC TO THE LFC2 RELAY

Access the PCM and monitor the LFCF PID.
Command the high speed fan ON.
Command the outputs OFF.
Command the low speed fan ON.
Command the outputs OFF.

Does the PID indicate a fault (yes) when either the high or low speed cooling fan output is commanded on and off?

Yes	No
GO to KF23.	INSTALL a new LFC1 relay.

KF23 CHECK THE VPWR VOLTAGE TO LFC2 RLY

LFC2 Relay connector disconnected.
Key in ON position.

Measure the voltage between:

(+) LFC2 Relay Connector, Harness Side	(-)
VPWR	Ground

Is the voltage greater than 10.5 V?

Yes	No
Key in OFF position. GO to KF24.	Key in OFF position. REPAIR the open circuit.

KF24 CHECK THE LFC CIRCUIT BETWEEN THE LOW SPEED FC RELAY(S)

Measure the resistance between:

(+) LFC1 Relay Connector, Harness Side	(-) LFC2 Relay Connector, Harness Side
LFC	LFC

Is the resistance less than 5 ohms?

Yes	No
INSTALL a new LFC relay. (INSTALL new LFC relays).	REPAIR the open circuit.

KF25 KOEO AND KOER DTCS P0482 OR P1477: CHECK THE VPWR VOLTAGE TO MFC1 RLY

NOTE: This application has 2 relays wired to the MFC circuit. This procedure may call out MFC1 and MFC2 relays. Either of the relays may be used as the number 1, with the other relay being number 2.

MFC1 Relay connector disconnected.
Key in ON position.

Measure the voltage between:

(+) MFC1 Relay Connector, Harness Side	(-)
VPWR	Ground

Is the voltage greater than 10.5 V?

Yes	No
Key in OFF position. GO to KF26.	Key in OFF position. REPAIR the open circuit.

KF26 CHECK FOR MFC CIRCUIT CYCLING

Connect a non-powered test lamp between:

(+) MFC1 Relay Connector, Harness Side	(-) MFC1 Relay Connector, Harness Side
VPWR	MFC

Enter output test mode. Refer to OUTPUT TEST MODE (OTM) .
Command the low speed fan ON.
Command the high speed fan ON.
Command the outputs OFF.

Does the test lamp illuminate on and off when either the low or high speed cooling fan output is commanded on and off?

Yes	No
INSTALL a new MFC1 RLY at end of diagnostics. Leave RLY disconnected GO to KF31.	Leave the test lamp connected GO to KF27.

KF27 CHECK FOR MFC CIRCUIT CYCLING WITH THE MFC2 RLY DISCONNECTED

Connect a non-powered test lamp between:

(+) MFC1 Relay Connector, Harness Side	(-) MFC1 Relay Connector, Harness Side
VPWR	MFC

MFC2 Relay connector disconnected.
Command the low speed fan ON.
Command the high speed fan ON.
Command the outputs OFF.

Does the test lamp illuminate on and off when either the low or high speed cooling fan output is commanded on and off?

Yes	No
INSTALL a new MFC2 relay.	GO to KF28.

KF28 CHECK THE MFC CIRCUIT FOR A SHORT TO POWER IN THE HARNESS

PCM connector disconnected.
Key in ON position.

Measure the voltage between:

(+) MFC1 Relay Connector, Harness Side	(-)
MFC	Ground

Is the voltage less than 1 V?

Yes	No
Key in OFF position. GO to KF29.	Key in OFF position. REPAIR the short circuit.

KF29 CHECK THE MFC CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS

Diagnostic tool connector disconnected.

Measure the resistance between:

(+) MFC1 Relay Connector, Harness Side	(-)
MFC	Ground

Is the resistance greater than 10K ohms?

Yes	No
GO to KF30.	REPAIR the short circuit.

KF30 CHECK THE MFC CIRCUIT FOR AN OPEN IN THE HARNESS

Measure the resistance between:

(+) MFC1 Relay Connector, Harness Side	(-) PCM Connector, Harness Side
MFC	MFC

Is the resistance less than 5 ohms?

Yes	No
INSTALL a new PCM. REFER to FLASH ELECTRICALLY ERASABLE PROGRAMMABLE READ ONLY MEMORY (EEPROM) .	REPAIR the open circuit.

KF31 VERIFY THERE IS NOT AN OPEN IN THE CIRCUIT SPECIFIC TO THE MFC2 RELAY

Access the PCM and monitor the MFCF PID.
Command the high speed fan ON.
Command the outputs OFF.
Command the low speed fan ON.
Command the outputs OFF.

Does the PID indicate a fault (yes) when either the high or low speed Cooling fan output is commanded on and off?

Yes	No
GO to KF32.	INSTALL a new MFC relay.

KF32 CHECK THE VPWR VOLTAGE TO MFC2 RLY

MFC2 Relay connector disconnected.
Key in ON position.

Measure the voltage between:

(+) MFC2 Relay Connector, Harness Side	(-)
VPWR	Ground

Is the voltage greater than 10.5 V?

Yes	No
Key in OFF position. GO to KF33.	Key in OFF position. REPAIR the open circuit.

KF33 CHECK THE MFC CIRCUIT BETWEEN THE MEDIUM SPEED FC RELAY(S)

Measure the resistance between:

(+) MFC1 Relay Connector, Harness Side	(-) MFC2 Relay Connector, Harness Side
MFC	MFC

Is the resistance less than 5 ohms?

Yes	No
INSTALL a new HFC relay(s).	REPAIR the open circuit.

KF34 KOEO AND KOER DTCS P0481 OR P1479: CHECK THE VPWR VOLTAGE TO HFC1 RLY

NOTE: This application has 2 relays wired to the HFC circuit. This procedure may call out HFC1 and HFC2 relays. Either of the relays may be used as the number 1, with the other relay being number 2.

HFC1 Relay connector disconnected.
Key in ON position.

Measure the voltage between:

(+) HFC1 Relay Connector, Harness Side	(-)
VPWR	Ground

Is the voltage greater than 10.5 V?

Yes	No
Key in OFF position. GO to KF35.	Key in OFF position. REPAIR the open circuit.

KF35 CHECK FOR HFC CIRCUIT CYCLING

Connect a non-powered test lamp between:

(+) HFC1 Relay Connector, Harness Side	(-) HFC1 Relay Connector, Harness Side
VPWR	HFC

Enter output test mode. Refer to OUTPUT TEST MODE (OTM) .
Command the low speed fan ON.
Command the high speed fan ON.
Command the outputs OFF.

Does the test lamp illuminate on and off when either the low or high speed cooling fan output is commanded on and off?

Yes	No
INSTALL a new HFC1 RLY at end of diagnostics. Leave RLY disconnected, GO to KF40.	Leave the test lamp connected, GO to KF36

KF36 CHECK FOR HFC CIRCUIT CYCLING WITH THE HFC2 RLY DISCONNECTED

Connect a non-powered test lamp between:

(+) HFC1 Relay Connector, Harness Side (-)	(-) HFC1 Relay Connector, Harness Side (-)
VPWR	HFC

HFC2 Relay connector disconnected.
Command the low speed fan ON.
Command the high speed fan ON.
Command the outputs OFF.

Does the test lamp illuminate on and off when either the low or high speed cooling fan output is commanded on and off?

Yes	No
INSTALL a new HFC2 relay.	GO to KF37.

KF37 CHECK THE HFC CIRCUIT FOR A SHORT TO POWER IN THE HARNESS

PCM connector disconnected.
Key in ON position.

Measure the voltage between:

(+) HFC1 Relay Connector, Harness Side	(-)
HFC	Ground

Is the voltage less than 1 V?

Yes	No
Key in OFF position. GO to KF38	Key in OFF position. REPAIR the short circuit.

KF38 CHECK THE HFC CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS

Diagnostic tool connector disconnected.

Measure the resistance between:

(+) HFC1 Relay Connector, Harness Side	(-)
HFC	Ground

Is the voltage less than 1 V?

Yes	No
GO to KF39.	REPAIR the short circuit.

KF39 CHECK THE HFC CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS

Measure the resistance between:

(+) HFC1 Relay Connector, Harness Side	(-) HFC1 Relay Connector, Harness Side
HFC	HFC

Is the resistance less than 5 ohms

Yes	No
INSTALL a new PCM. REFER to FLASH ELECTRICALLY ERASABLE PROGRAMMABLE READ ONLY MEMORY (EEPROM) .	REPAIR the open circuit.

KF40 VERIFY THERE IS NOT AN OPEN IN THE CIRCUIT SPECIFIC TO THE HFC2 RELAY

Access the PCM and monitor the MFCF PID.
Command the high speed fan ON.
Command the outputs OFF.
Command the low speed fan ON.
Command the outputs OFF.

Does the PID indicate a fault (yes) when either the high or low speed cooling fan output is commanded on and off?

Yes	No
GO to KF41.	INSTALL a new HFC1 relay.

KF41 CHECK THE VPWR VOLTAGE TO HFC2 RLY

HFC2 Relay connector disconnected.
Key in ON position.

Measure the voltage between:

(+) HFC2 Relay Connector, Harness Side	(-)
VPWR	Ground

Is the voltage greater than 10.5 V?

Yes	No
Key in OFF position. GO to KF42.	Key in OFF position. REPAIR the open circuit.

KF42 CHECK THE HFC CIRCUIT BETWEEN THE HIGH SPEED FC RELAY(S)

Measure the resistance between:

(+) HFC1 Relay Connector, Harness Side	(-) HFC2 Relay Connector, Harness Side
HFC	HFC

Is the resistance less than 5 ohms?

Yes	No
INSTALL a new HFC relay(s).	REPAIR the open circuit.

KF43 CONTINUOUS MEMORY DTCS P0480 OR P1474: CHECK THE LFC CIRCUIT FOR AN INTERMITTENT OPEN OR SHORT TO POWER

A/C and defrost off.
L Fan Motor connector disconnected.
R Fan Motor connector disconnected.
LFC Relay connector disconnected.

Connect a non-powered test lamp between:

(+) LFC Relay Connector, Harness Side	(-) LFC Relay Connector, Harness Side
VPWR - Pin 1	LFC - Pin 2

Key in ON position.
Enter output test mode. Refer to OUTPUT TEST MODE (OTM) .
Command the low speed fan ON.
NOTE: If the test lamp does not turn on, Command the high speed fan ON.
Observe the test lamp for an indication of a fault while completing the following. Note that the lamp turns Off when a fault is detected.
- Shake, wiggle, and bend the LFC circuit(s).
- Shake, wiggle, and bend the VPWR circuit to the LFC relay.
- Inspect the LFC RLY component for signs of damage.

Is a fault indicated?

Yes	No
Key in OFF position. ISOLATE the fault and REPAIR as necessary.	GO to KF44.

KF44 CHECK THE LFC CIRCUIT FOR AN INTERMITTENT SHORT TO GROUND

Key in ON position.
Command the outputs OFF.
Observe the test lamp for an indication of a fault while completing the following. Note that the lamp turns on when a fault is detected.
- Shake, wiggle, and bend the LFC circuit(s).
- Lightly tap on the LFC RLY to simulate road shock.

Is a fault indicated?

Yes	No
Key in OFF position. ISOLATE the fault and REPAIR as necessary.	Key in OFF position. Unable to duplicate or identify the fault at this time. GO to PINPOINT TEST Z STEP 1 .

KF45 CONTINUOUS MEMORY DTCS P0481 OR P1479: CHECK THE HFC CIRCUIT FOR AN INTERMITTENT OPEN OR SHORT TO POWER

A/C and defrost off.
L Fan Motor connector disconnected.
R Fan Motor connector disconnected.
HFC Relay connector disconnected.

Connect a non-powered test lamp between:

(+) HFC Relay Connector, Harness Side	(-) HFC Relay Connector, Harness Side
VPWR - Pin 1	HFC - Pin 2

Key in ON position.
Enter output test mode. Refer to OUTPUT TEST MODE (OTM) .
Command the high speed fan ON.
NOTE: If the test lamp does not turn on, Command the low speed fan ON.
Observe the test lamp for an indication of a fault while completing the following. Note that the lamp turns Off when a fault is detected.
- Shake, wiggle, and bend the HFC circuit(s).
- Shake, wiggle, and bend the VPWR circuit to the HFC relay.
- Lightly tap on the HFC RLY to simulate road shock.

Is a fault indicated?

Yes	No
Key in OFF position. ISOLATE the fault and REPAIR as necessary.	GO to KF46.

KF46 CHECK THE HFC CIRCUIT FOR AN INTERMITTENT SHORT TO GROUND

Key in ON position.
Command the outputs OFF.
Observe the test lamp for an indication of a fault while completing the following. Note that the lamp illuminates when a fault is detected.
- Shake, wiggle, and bend the HFC circuit(s).

Is a fault indicated?

Yes	No
Key in OFF position. ISOLATE the fault and REPAIR as necessary.	Key in OFF position. Unable to duplicate or identify the fault at this time. GO to PINPOINT TEST Z STEP 1 .

KF47 CONTINUOUS MEMORY DTCS P0482 OR P1477: CHECK THE MFC CIRCUIT FOR AN INTERMITTENT OPEN OR SHORT TO POWER

A/C and defrost off.
L Fan Motor connector disconnected.
R Fan Motor connector disconnected.
MFC Relay connector disconnected.

Connect a non-powered test lamp between:

(+) MFC Relay Connector, Harness Side	(-) MFC Relay Connector, Harness Side
VPWR - Pin 1	MFC - Pin 2

Key in ON position.
Enter output test mode. Refer to OUTPUT TEST MODE (OTM) .
Command the low speed fan ON.
NOTE: If the test lamp does not turn on, Command the high speed fan ON.
Observe the test lamp for an indication of a fault while completing the following. Note that the lamp turns Off when a fault is detected.
- Shake, wiggle, and bend the MFC circuit(s).
- Shake, wiggle, and bend the VPWR circuit to the MFC relay.
- Inspect the MFC RLY component for signs of damage.

Is a fault indicated?

Yes	No
Key in OFF position. ISOLATE the fault and REPAIR as necessary.	GO to KF48.

KF48 CHECK THE MFC CIRCUIT FOR AN INTERMITTENT SHORT TO GROUND

Key in ON position.
Command the outputs OFF.
Observe the test lamp for an indication of a fault while completing the following. Note that the lamp turns Off when a fault is detected.
- Shake, wiggle, and bend the MFC circuit(s).

Is a fault indicated?

Yes	No
Key in OFF position. ISOLATE the fault and REPAIR as necessary.	Key in OFF position. Unable to duplicate or identify the fault at this time. GO to PINPOINT TEST Z STEP 1 .

KF49 CONTINUOUS MEMORY DTCS P0480 OR P1474: CHECK THE LFC CIRCUIT FOR AN INTERMITTENT OPEN OR SHORT TO POWER

NOTE: This application has 2 relays wired to the LFC circuit. This procedure may call out LFC1 and LFC2 relays. Either of the relays may be used as the number 1, with the other relay being number 2.

AC and defroster OFF.
L Fan Motor connector disconnected.
R Fan Motor connector disconnected.
LFC1 Relay connector disconnected.

Connect a non-powered test lamp between:

(+) LFC1 Relay Connector, Harness Side	(-) LFC1 Relay Connector, Harness Side
VPWR	LFC

Key in ON position.
Enter output test mode. Refer to OUTPUT TEST MODE (OTM) .
Command the low speed fan ON.
NOTE: If the test lamp does not turn on, Command the high speed fan ON.
Observe the test lamp for an indication of a fault while completing the following. Note that the lamp turns OFF when a fault is detected.
- Shake, wiggle, and bend the LFC circuit between the PCM and both low speed FC relays.
- Shake, wiggle, and bend the VPWR circuit to both low speed FC relays.
- Lightly tap on the Low Speed FC relay that is still connected to simulate road shock.

Is a fault indicated?

Yes	No
Key in OFF position. ISOLATE the fault and REPAIR as necessary.	GO to KF50.

KF50 CHECK THE LFC CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS

Key in ON position.
Command the outputs OFF.
Exit output test mode.
Observe the test lamp for an indication of a fault while completing the following. Note that the lamp turns ON when a fault is detected.
- Shake, wiggle, and bend the LFC circuit between the PCM and both low speed FC relays.
Inspect Low Speed FC Relay that is disconnected for intermittent concerns.

Is a fault indicated?

Yes	No
Key in OFF position. ISOLATE the fault and REPAIR as necessary.	Key in OFF position. GO to PINPOINT TEST Z STEP 1 .

KF51 CONTINUOUS MEMORY DTCS P0482 OR P1477: CHECK THE MFC CIRCUIT FOR AN INTERMITTENT OPEN OR SHORT TO POWER

NOTE: This application has 2 relays wired to the MFC circuit. This procedure may call out MFC1 and MFC2 relays. Either of the relays may be used as the number 1, with the other relay being number 2.

AC and defroster OFF.
L Fan Motor connector disconnected.
R Fan Motor connector disconnected.
MFC1 Relay connector disconnected.

Connect a non-powered test lamp between:

(+) MFC1 Relay Connector, Harness Side	(-) MFC1 Relay Connector, Harness Side
VPWR	MFC

Key in ON position.
Enter output test mode. Refer to OUTPUT TEST MODE (OTM) .
Command the low speed fan ON.
NOTE: If the test lamp does not turn on, Command the high speed fan ON.
Observe the test lamp for an indication of a fault while completing the following. Note that the lamp turns OFF when a fault is detected.
- Shake, wiggle, and bend the MFC circuit between the PCM and both medium speed FC relays.
- Shake, wiggle, and bend the VPWR circuit to both medium speed FC relays.
- Lightly tap on the Medium Speed FC relay that is still connected to simulate road shock.

Is a fault indicated?

Yes	No
Key in OFF position. ISOLATE the fault and REPAIR as necessary.	GO to KF52.

KF52 CHECK THE MFC CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS

Key in ON position.
Command the outputs OFF.
Exit output test mode.
Observe the test lamp for an indication of a fault while completing the following. Note that the lamp turns ON when a fault is detected.
- Shake, wiggle, and bend the MFC circuit between the PCM and both medium speed FC relays.
Inspect Medium Speed FC relay that is disconnected for intermittent concerns.

Is a fault indicated?

Yes	No
Key in OFF position. ISOLATE the fault and REPAIR as necessary.	Key in OFF position. GO to PINPOINT TEST Z STEP 1 .

KF53 CONTINUOUS MEMORY DTCS P0481 OR P1479: CHECK THE HFC CIRCUIT FOR AN INTERMITTENT OPEN OR SHORT TO POWER

NOTE: This application has 2 relays wired to the HFC circuit. This procedure may call out HFC1 and HFC2 relays. Either of the relays may be used as the number 1, with the other relay being number 2.

AC and defroster OFF.
L Fan Motor connector disconnected.
R Fan Motor connector disconnected.
HFC1 Relay connector disconnected.

Connect a non-powered test lamp between:

(+) HFC1 Relay Connector, Harness Side	(-) HFC1 Relay Connector, Harness Side
VPWR	HFC

Key in ON position.
Enter output test mode. Refer to OUTPUT TEST MODE (OTM) .
Command the low speed fan ON.
NOTE: If the test lamp does not turn on, Command the high speed fan ON.
Observe the test lamp for an indication of a fault while completing the following. Note that the lamp turns OFF when a fault is detected.
- Shake, wiggle, and bend the HFC circuit between the PCM and both High Speed FC relays.
- Shake, wiggle, and bend the VPWR circuit to both high speed FC relays.
- Lightly tap on the High Speed FC relay that is still connected to simulate road shock.

Is a fault indicated?

Yes	No
Key in OFF position. ISOLATE the fault and REPAIR as necessary.	GO to KF54.

KF54 CHECK THE HFC CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS

Key in ON position.
Command the outputs OFF.
Exit output test mode.
Observe the test lamp for an indication of a fault while completing the following. Note that the lamp turns ON when a fault is detected.
- Shake, wiggle, and bend the HFC circuit between the PCM and both High Speed FC relays.
Inspect High Speed FC Relay that is disconnected for intermittent concerns.

Is a fault indicated?

Yes	No
Key in OFF position. ISOLATE the fault and REPAIR as necessary.	Key in OFF position. GO to PINPOINT TEST Z STEP 1 .

KF55 COOLING FAN ALWAYS RUNS (NO DTCS): VERIFY THE FAN IS NOT ON BECAUSE OF A/C HIGH PRESSURE SWITCH INPUT TO THE PCM

Key on engine running.
Access the PCM and monitor the ACP PID.

Is the PID state CLOSED?

Yes	No
Key in OFF position. The PCM will turn the fan on when the medium pressure, normally open contacts of the ACHP switch are closed. GO to KF66.	Input OK GO to KF56.

KF56 COOLING FAN CONCERN (NO DTCS): CHECK THE FAN CONTROL PRIMARY CIRCUITS

Verify that AC is OFF.
Verify engine temperature is below the temperature where the Cooling fan would come on.
Key in ON position.
NOTE: Chose the PIDs below as appropriate, according to which circuits the vehicle has.
Access the PCM and monitor the LFCF, MFCF and HFCF PIDs.

Does either PID indicate a fault?

Yes	No
Primary circuit(s) Fault found. GO to KF57.	For all except Ranger: PCM Primary circuit(s) is OK. To check for secondary wiring, REFER to the ENGINE COOLING for cooling system diagnostics. For Ranger: GO to KF59.

KF57 DID THE LFCF PID INDICATE A FAULT?

Did the LFCF PID indicate a fault?

Yes	No
Low Fan Control (LFC) Primary Circuit Failure For Freestar/Monterey, GO to KF16. For all others, GO to KF1.	GO to KF58.

KF58 DID THE MFCF PID INDICATE A FAULT?

Did the MFCF PID indicate a fault?

Yes	No
Medium Fan Control (MFC) Primary Circuit Failure For Focus, and Freestar/Monterey, GO to KF25. For all others, GO to KF6.	High Fan Control (HFC) Primary Circuit Failure For Taurus, Sable, Escape 3.0L, Mariner 3.0L, and Ford GT, GO to KF34. For all others, GO to KF11.

KF59 IS THE SYMPTOM: COOLING FAN ALWAYS RUNS?

Is the symptom: cooling fan always runs?

Yes	No
GO to KF65.	GO to KF60.

KF60 ELECTRIC COOLING FAN CONCERN (WITH NO DTCS): ELECTRIC COOLING FAN FUNCTIONAL CHECK

Key in ON position.
Enter output test mode. Refer to OUTPUT TEST MODE (OTM) .
Command the low speed fan ON.

Does the fan operate?

Yes	No
Key in OFF position. All Cooling fan circuit checks are OK. RETURN to SYMPTOM CHARTS - GASOLINE MODELS to continue diagnosis.	GO to KF61.

KF61 FAN INOPERATIVE: COMMAND THE LOW SPEED FAN ON AND CHECK FOR VOLTAGE TO THE CF

Key in OFF position.
CF Motor connector disconnected.
Key in ON position.
Enter output test mode. Refer to OUTPUT TEST MODE (OTM) .
Command the low speed fan ON.

Measure the voltage between:

(+) CF Motor Connector, Harness Side	(-)
FAN PWR	Ground

Is the voltage greater than 10.5 V?

Yes	No
Key in OFF position. GO to KF62.	Key in OFF position. GO to KF63.

KF62 CHECK THE GROUND CIRCUIT TO COOLING FAN

Measure the resistance between:

(+) CF Motor Connector, Harness Side	(-)
GND	Ground

Is the resistance less than 5 ohms?

Yes	No
INSTALL a new CF motor.	REPAIR the open circuit.

KF63 CHECK THE B+ VOLTAGE TO FC RLY

FC Relay connector disconnected.

Measure the voltage between:

(+) FC Relay Connector, Harness Side	(-)
B+	Ground

Is the voltage greater than 10.5 V?

Yes	No
GO to KF64.	REPAIR the open circuit. B+ circuit fault. CHECK the condition of the related fuse/fuse links. If OK, REPAIR the open circuit. If the fuse/fuse link is damaged, CHECK the circuit for short to ground before replacing.

KF64 CHECK THE FAN PWR CIRCUIT FOR AN OPEN IN THE HARNESS

Measure the resistance between:

(+) FC Relay Connector, Harness Side	(-) CF Motor Connector, Harness Side
FAN PWR	FAN PWR

Is the resistance less than 5 ohms?

Yes	No
INSTALL a new FC relay.	REPAIR the open circuit.

KF65 CHECK FOR FC RLY CONTACTS ALWAYS CLOSED

NOTE: Verify the A/C and defrost are off.

FC Relay connector disconnected.
Key in ON position.

Does the fan run with the key in the ON position?

Yes	No
Key in OFF position. REPAIR the short circuit to PWR.	Key in OFF position. INSTALL a new FC relay.

KF66 CHECK THE A/CHPSW (MEDIUM PRESSURE, NORMALLY OPEN CONTACTS)

A/CHPSW connector disconnected.
Key in ON position.
Access the PCM and monitor the ACP PID.

Is the PID state CLOSED?

Yes	No
Key in OFF position. GO to KF67.	Key in OFF position. CONNECT the A/CHPSW. REFER to CLIMATE CONTROL SYSTEM to diagnose the A/C system pressure. If OK, INSTALL a new A/CHPSW.

KF67 CHECK THE A/CPSW CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS

PCM connector disconnected.

Measure the resistance between:

(+) A/CHPSW Connector, Harness Side	(-)
A/CPSW	Ground

Is the resistance greater than 10K ohms?

Yes	No
Verify the results of the previous test steps. RETURN to SYMPTOM CHARTS - GASOLINE MODELS to continue diagnosis. If OK, INSTALL a new PCM. REFER to FLASH ELECTRICALLY ERASABLE PROGRAMMABLE READ ONLY MEMORY (EEPROM) .	REPAIR the short circuit to GND.